Roborock’s Error 42 maintenance-brush guidance is for the S7 MaxV Ultra, S7 Max Ultra, and S8 Pro Ultra. The same number may mean something different on another model or brand.
Identify which side stops
- If the brush stops on the left, Roborock says it may be jammed. Remove any item obstructing it.
- If the brush stops on the right, Roborock says the filter may be blocked or incorrectly installed. Clean it and reinstall it correctly for the model.
Follow only the branch that matches the side reported by the robot; the two checks address different possible causes. The support page does not tell owners to swap the left and right steps or to disassemble the brush assembly.
Keep the check external and use the exact model’s instructions. A clean brush or filter does not establish that a motor has failed. If the error persists, contact Roborock support rather than opening the robot or ordering a part from the code alone.
When contacting support, give the exact model, which side stopped, and whether clearing the brush or cleaning and reseating the filter changed the alert. The published guidance covers only the three models named above; it does not establish Error 42 behavior or maintenance-brush fitment for another Roborock family.